以钛铁矿制备Fe3O4/TiO2磁性复合材料及光催化性能

Photocatalytic property of Fe3O4/TiO2magnetic composite prepared from ilmenite

采用硫酸法提取钛铁矿的产物制备纳米TiO2和聚乙烯亚胺(PEI)修饰的Fe3O4(Fe3O4/PEI),进一步采用组装法制备Fe3O4/TiO2复合材料。表征复合材料的物相结构、化学组成、粒径、Zeta电位和磁性能,并以降解罗丹明B溶液的效果评价其光催化性能。结果表明,PEI修饰增强了Fe3O4与TiO2的结合力;随着TiO2与Fe3O4/PEI质量比的增大,复合材料的TiO2含量增多,在紫外光下光催化活性增强;TiO2中的微量Fe离子赋予复合材料良好的可见光催化活性,投料比为20时性能最佳。适中的尺寸、快速的磁响应能力,以及在5次重复使用中良好的催化稳定性和高于90%的收率,显示该复合材料具有良好的工业应用前景。

Fe3O4/TiO2magnetic composites were fabricated by assembly method using nano-sized TiO2and poly(ethyleneimine)-modified Fe3O4(Fe3O4/PEI),which were prepared by using the products extracted from ilmenite with sulfuric acid.The phase structure,chemical composition,size,Zeta potential and magnetic property of the composite were characterized,and the degradation efficiency of Rhodamine B was used to evaluate the photocatalytic performance of the composites.The results showed that the interaction between Fe3O4 and TiO2 was greatly enhanced by modification with PEI due to the electrostatic attraction.As the mass ratio of TiO2and Fe3O4/PEI enlarged,the composite had an elevated TiO2content and improved photocatalytic activity under UV irradiation.Also the composites exhibited high photocatalytic activity as exposed to visible light due to the doped Fe ions in TiO2,and the one with a mass ratio of 20showed the best photocatalytic performance.The catalyst had a moderate size,quick response to the magnetite,good catalytic stability and recovery efficiency of over 90%in five recycle uses.All these features made the catalyst promising in industrial application.